UMBC Computer Science and Electrical Engineering Departmenthttp://hdl.handle.net/11603/502019-09-15T12:09:48Z2019-09-15T12:09:48ZEnhancements to Model-reduced Fluid SimulationGerszewski, DanKavan, LadislavSloan, Peter-PikeBargteil, Adam W.http://hdl.handle.net/11603/145472019-09-13T07:45:38Z2013-11-06T00:00:00ZEnhancements to Model-reduced Fluid Simulation
Gerszewski, Dan; Kavan, Ladislav; Sloan, Peter-Pike; Bargteil, Adam W.
We present several enhancements to model-reduced fluid simulation that allow improved simulation bases and two-way solid-fluid
coupling. Specifically, we present a basis enrichment scheme that
allows us to combine data driven or artistically derived bases with
more general analytic bases derived from Laplacian Eigenfunctions. We handle two-way solid-fluid coupling in a time-splitting
fashion—we alternately timestep the fluid and rigid body simulators, while taking into account the effects of the fluid on the rigid
bodies and vice versa. We employ the vortex panel method to handle solid-fluid coupling and use dynamic pressure to compute the
effect of the fluid on rigid bodies.
2013-11-06T00:00:00ZAutomatic Construction of Coarse, High-Quality Tetrahedralizations that Enclose and Approximate Surfaces for AnimationStuart, David A.Levine, Joshua A.Jones, BenBargteil, Adam W.http://hdl.handle.net/11603/145462019-09-13T07:45:36Z2013-11-06T00:00:00ZAutomatic Construction of Coarse, High-Quality Tetrahedralizations that Enclose and Approximate Surfaces for Animation
Stuart, David A.; Levine, Joshua A.; Jones, Ben; Bargteil, Adam W.
Embedding high-resolution surface geometry in coarse control meshes is a standard approach to achieving high-quality computer animation at low computational expense. In this paper we present an effective, automatic method for generating such control meshes. The resulting high-quality, tetrahedral meshes enclose and approximate an input surface mesh, avoiding extrapolation artifacts and ensuring that the resulting coarse volumetric meshes are adequate collision proxies. Our approach comprises three steps: we begin with a tetrahedral mesh built from the body-centered cubic lattice that tessellates the bounding box of the input surface; we then perform a sculpting phase that carefully removes elements from the lattice; and finally a variational vertex adjustment phase iteratively adjusts vertex positions to more closely approximate the surface geometry. Our approach provides explicit trade-offs between mesh quality, resolution, and surface approximation. Our experiments demonstrate the technique can be used to build high-quality meshes appropriate for simulations within games.
2013-11-06T00:00:00ZDynamic SpritesJones, BenPopovic, JovanMcCann, JamesLi, WilmotBargteil, Adamhttp://hdl.handle.net/11603/145452019-09-13T07:45:34Z2013-11-06T00:00:00ZDynamic Sprites
Jones, Ben; Popovic, Jovan; McCann, James; Li, Wilmot; Bargteil, Adam
Traditional methods for creating dynamic objects and
characters from static drawings involve careful tweaking
of animation curves and/or simulation parameters. Sprite
sheets offer a more drawing-centric solution, but they do
not encode timing information or the logic that determines
how objects should transition between poses and cannot
generalize outside the given drawings. We present an approach for creating dynamic sprites that leverages sprite
sheets while addressing these limitations. In our system,
artists create a drawing, deform it to specify a small number of example poses, and indicate which poses can be
interpolated. To make the object move, we design a procedural simulation to navigate the pose manifold in response to external or user-controlled forces. Powerful
artistic control is achieved by allowing the artist to specify both the pose manifold and how it is navigated, while
physics is leveraged to provide timing and generality. We
used our method to create sprites with a range of different
dynamic properties.
2013-11-06T00:00:00ZFluid Simulation on Unstructured Quadrilateral Surface MeshesBhattacharya, HaimasreeLevine, Joshua A.Bargteil, Adam W.http://hdl.handle.net/11603/145442019-09-13T07:45:31ZFluid Simulation on Unstructured Quadrilateral Surface Meshes
Bhattacharya, Haimasree; Levine, Joshua A.; Bargteil, Adam W.
In this paper, we present a method for fluid simulation on unstructured quadrilateral surface meshes. We solve the Navier-Stokes
equations by performing the traditional steps of fluid simulation,
semi-Lagrangian advection and pressure projection, directly on the
surface. We include level-set based front-tracking for visualizing
“liquids,” while we use densities to visualize “smoke.” We demonstrate our method on a variety of meshes and create an assortment
of visual effects